Projecting optical system

Abstract

A projecting optical system for decreasing a height of an optical system is provided. The system includes a lamp for irradiating light, a color divider for dividing colors of light irradiated from the lamp, an illumination mixer for irradiating the light with equal light intensity, a channel-changing prism for changing a channel of light irradiated from the illumination mixer to upward and downward, and a TIR prism for changing a direction and angle of light to a predetermined direction and angle.

What is claimed is: 
     
       1. A projecting optical system, comprising:
 a lamp configured to irradiate light; 
 a color divider configured to divide colors of light irradiated from the lamp; 
 a illumination mixer configured to irradiate the light received from the color divider with equal light intensity; 
 a channel-changing prism configured to receive light irradiated from the illumination mixer and to provide a predetermined distance between an axis of incidence light and an axis of light emitted by the channel-changing prism by rotating; 
 a rotation device configured to rotate the channel-changing prism; and 
 a TIR prism for changing a direction and angle of light to a predetermined direction and angle, wherein the axis of incidence light and the axis of light emitted by the channel-changing prism are substantially parallel. 
 
     
     
       2. The projecting optical system of  claim 1 , further comprising a reflective mirror for changing the channel of light such that the light irradiated from the lamp is entered into the color divider. 
     
     
       3. The projecting optical system of  claim 1 , wherein at least one first illumination lens and second illumination lens for controlling the intensity of light are provided between the channel-changing prism. 
     
     
       4. The projecting optical system of  claim 1 , wherein the color divider comprises a plurality of optical means formed in a disk or cylindrical form and rotatably provided for selectively transmitting or reflecting a color. 
     
     
       5. A projector having a DMD panel comprising the projecting optical system of  claim 1 . 
     
     
       6. The projector of  claim 5 , further comprising a reflective mirror for changing the channel of light such that the light irradiated from the lamp is entered into the color divider. 
     
     
       7. The projector of  claim 5 , wherein at least one first illumination lens and second illumination lens for controlling the intensity of light are provided between the channel-changing prism. 
     
     
       8. The projector of  claim 5 , wherein the color divider comprises a plurality of optical means formed in a disk or cylindrical form and rotatably provided for selectively transmitting or reflecting a color. 
     
     
       9. The projector of  claim 5 , wherein the channel-changing prism is rotatably provided for controlling step difference of emission light. 
     
     
       10. The projector of  claim 5 , wherein the TIR prism is inclined at a predetermined angle vertically and horizontally for maintaining the predetermined incidence angle of light required by the DMD panel. 
     
     
       11. The projecting optical system of  claim 5 , wherein the predetermined distance extends in a substantially vertical direction. 
     
     
       12. The projecting optical system of  claim 5 , wherein the channel-changing prism comprises two substantially parallel reflective planes that provide the predetermined distance between the axis of incidence light and the axis of light emitted by the channel-changing prism. 
     
     
       13. The projecting optical system of  claim 1 , wherein the predetermined distance extends in a substantially vertical direction. 
     
     
       14. The projecting optical system of  claim 1 , wherein the channel-changing prism comprises two substantially parallel reflective planes that provide the predetermined distance between the axis of incidence light and the axis of light emitted by the channel-changing prism. 
     
     
       15. A projecting optical system, comprising:
 a lamp configured to irradiate light; 
 a illumination mixer configured to irradiate the light received from the lamp with equal light intensity; 
 a channel-changing prism configured to receive light irradiated from the illumination mixer and to provide a predetermined distance between an axis of incidence light and an axis of light emitted by the channel-changing prism by rotating; 
 a rotation device configured to rotate the channel-changing prism; and 
 a prism for changing a direction and angle of light to a predetermined direction and angle, wherein the axis of incidence light and the axis of light emitted by the channel-changing prism are substantially parallel. 
 
     
     
       16. The projecting optical system of  claim 15 , wherein the predetermined distance extends in a substantially vertical direction. 
     
     
       17. The projecting optical system of  claim 15 , wherein the channel-changing prism comprises two substantially parallel reflective planes that provide the predetermined distance between the axis of incidence light and the axis of light emitted by the channel-changing prism. 
     
     
       18. A projector having a DMD panel comprising the projecting optical system of  claim 15 .